An 86-year-old woman has been charged over the death of six-year-old Indie Armstrong, who died after she was struck by a car in a supermarket car park on Queensland's Sunshine Coast.

It will be alleged that the silver hatchback reversed and hit Indie, her eight-year-old sister Lily, mother Emily and grandmother Sandy Bampton as they stood at a pedestrian crossing in front of Coles at Nambour on June 17.

Indie was taken to Nambour Hospital where she later died.

Her sister suffered a non-life threatening lower leg injury and was taken to Sunshine Coast University Hospital.